https://openjdk.java.net/ 
public interface java.security.interfaces.RSAPrivateKey extends java.security.PrivateKey, java.security.interfaces.RSAKey
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: java.security.interfaces.RSAPrivateKey
  super_class: java.lang.Object
{
  public static final long serialVersionUID;
    descriptor: J
    flags: (0x0019) ACC_PUBLIC, ACC_STATIC, ACC_FINAL
    ConstantValue: 5187144804936595022

  public abstract java.math.BigInteger getPrivateExponent();
    descriptor: ()Ljava/math/BigInteger;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
}
SourceFile: "RSAPrivateKey.java"